US1708354A - Cave finder - Google Patents

Description

J. J. CABOT April 9, 1929.

CAVE FINDER Filed Oct. 13, 1927 Patented Apr. 9, 1929.

miran s'rn'ras 1,708,354 PATENT FFICE.

JAMES J'. CABO'I, OF CHARLESTON, WEST VIRGINIA.

GAVE FINDER.

Application led October 13, 1927. Serial No. 225,956.

The invention relates to a novel device for use in drilling and operating oil and gas wells. In some localities, it frequently happens that the sands or earth in which a well is drilled or is being drilled, will crumble in some places so that the earth falls to the bottom of the well, interfering with drilling or production, as the case may be. 'Ihe cavities in the side of the well formed by these crumblings, are known as caves and very often the difficulties can be much more effectively overcome if the well driller or operator is able to determine at what depth or depths, the cave or caves are sltuated. Hence, it is the object of my invention to provide a unique device for accomplishing this end.

With the foregoing in view, the invention resides in the novel subject matter hereinafter described and claimed, the description being supplemented by the accompanying drawing.

Fig. 1 is a side elevation of a cave finder constructed in accordance with my invention, showing the relation of parts which exists while the device is being lowered into a well.

Fig. 2 is a vertical longitudinal sectional view substantially on line 2-2 of Fig. 1.

Fig. 3 is a view similar to Fig. 2 but illustrating thevmovements which take place when the device encounters a cave.

The drawing above brieiiy described, illustrates one specific embodiment of my invention and while the details disclosed will be rather speciiically described, it is to be understood at the outset, that within the scope of the invention as claimed, variations may be made.

I make use of a vertically elongated body which is preferably in the form of a hollow rod 4, said rod being provided with a hollow cylindrical head 5 at its upper end to which a steel measuring line or the like 6 may be connected, for instance by a screw cap 7. The lower end of the rod 4 may also be provided with a head 8 which may if necessary be connected with a weight to assist in lowering the device into a well.

A number of pairs of toggle links are disposed longitudinally of the rods 4, the outer ends of said links being pivotally connected with the ends of the rod, while the inner ends of said links are slidably connected with each other. Spring means are cmployed urging these links outwardly toward the position of Fig. 3 but they are normally held against such outward movement by engagement with the wall ot a well. However, when a cave C is encountered as in Fig. 3, the toggle links move outwardly and I utilize this movement to operate a signal at the top of the well. Then, by reading the measuring line 6, the depth at which the cave is located, may be readily determined.

In the present showing, the upper links 9 are comparatively short and they are pivot-ed at 10 to lugs 11 projecting outwardly from the head 5. The lower links 12 however are ,of considerably greater length, the lower ends of these links being pivoted at 13 to the lugs 14 projecting from the head 8, while the upper ends of said links are slidably connected with the lower ends of the links 9. Preferably, these upper ends of the links 12 curve inwardly and are formed with longitudinal slots 15 slidably receiving rivets or the like 16 which pass through the lower ends of the links 9. These same members 16 pass through the upper ends of additional links 17 whose lower ends are pivotally connected in any desired manner as at 18, with a sleeve 19 which slidably surrounds the rod 4, said sleeve being urged upwardly by a coiled compression spring 20 which thrusts against a iiXed collar 21 on said rod. The links 17 normally diverge upwardly and hence the upward thrust of the spring 20, acting through the instrumentality of the sleeve 19 and the links 17, tends to outwardly Jforce the toggle links 9-12, away from the rod 4. The result is, that when the device reaches a cave such as C of Fig. 3, spring 20 acts to outwardly force the toggle links and when such outward forcing takes place, a signal is operated at the top of the well. The upward movement of the sleeve 19 and consequently the outward movement of the toggle links may be limited by an appropriate stop collar 22 on the rod 4.

In the preferred form of construction, a stationary annular contact 23 is mounted on the rod 4: and is insulated therefrom by a sleeve or the like 24. A spring arm 25, constituting a movable contact, normally engages the contact 28 and is secured at 26 to the sleeve 19. A wire 27 is shown connected at 28 with the contact 23 and leading to one terminal of a battery 29 which is disposed above ground. The other terminal of this battery is shown connected by a wire 30 with a signal light 31 which is in turn connected by a wire 32 with the measuring line 6. Hence, as long as contact 25 is in engagement with contact 23, the light 31 will remain illuminated. However, when a cave is encountered and the toggle links 9-12 move outwardly as in Fig. 3, contact 25 moves from engagement with contact n3 as shown in this view, thus breaking the circuit of the light 31 and extinguishing the latter, thereby notifying the operator that a cave has been reached. It is then an easy matter for him to read the measuring line 6 and determine the depth at which the cave is located. lf some other line be used instead of the measuring line 6, the depth at which the cave is located, may be determined by actually measuring the length oi line which was lowered into the well prior to extinguishing of the light 31, the measuring lbeing accomplished as the device is again withdrawn from the well. Such withdrawal is readily permitted, as upon upward movement of the device, eiiected by pull upon the line or the like 6, the uppermost toggle links 9 will engage the upper portion of the cave and will consequently be swung inwardly. Moreover, if the device is to be lowered further from the first cave encountered, this is readily permitted due to the inclination which the lower links 12 then assume, as when said device is permitted to descend further, said links 12 will engage the lower portion of the cave, thus again forcing the links inwardly. Upon such inward movement, contact 25 again engages contact 23 and the light 31 will remain illuminated as long as no additional cave is encountered.

As above stated, the details herein disclosed may be considered as preferred. However, within the scope of the invention as claimed, variations may of course be made.

I claim:

1. A well cave finder comprising a vertically elongated rod to be lowered into a well, a pair of toggle links extending longitudinally of said rod, the inner ends of said links being pivotally and slidably connected with each other while the upper and lower ends respectively of said links are pivotally connected with said rod, spring means tending to outwardly move said links away from said rod, such movement being prevented by the wall of the well until a cave is reached, and signal-controlling means operatively connected with said toggle links to be operated by outward movement thereof away from said rod.

2. A well cave finder comprising a vertically elongated rod to be lowered into a well, toggle links extending longitudinally of said rod and pivoted at their outer ends thereto, the inner ends of said links being pivotally and slidably connected, a sleeve slidable upon said rod, spring means acting to slide said sleeve in one direction, anl inclined link connecting said sleeve with the pivotally and slidably connected ends of said toggle links, and a signal-controlling means controlled by sliding of said sleeve.

3. A well cave finder comprising a vertically elongated rod to be lowered into a well, toggle links extending longitudinally ot' said rod and pivoted at their outer ends thereto, the inner ends of said links being pivotally and slidably connected, a sleeve slidable upon said rod, spring means acting to slide said sleevevin one direction, an inclined link connecting said sleeve with the pivotally and slidably connected ends of said toggle links, a contact arm secured to said sleeve and extending longitudinally therefrom, and a cont-act mounted on and insulated from said rod for co-action with said contact arm in controlling a signal circuit.

4. A well cave finder comprising a vertically elongated body, a signal-controlling member slidable on said body, an inclined link pivoted at one end to said member, a second inclined link pivoted at one end to the other end of the first named link, said second link being pivoted at its other end to said body, and spring means tending to move the pivotally connected ends of said links outwardly to effect sliding of said signal-controlling member.

5. A well cave nder comprising a vertically elongated rod to be lowered into a well, upper relatively short links pivoted at their upper ends to the upper 4portion of said rod and diverging downwardly with the latter, lower comparatively long links pivoted at their lower ends to the lower portion of said rod and diverging upwardly with respect to the latter, the upper ends of said long links being curved inwardly and having longitudinal slots in their curved ends, pivots passing through the lower ends of the short links and through the slots of the long links, additional links having their upper ends pivotally mounted on the last named pivots, said additional links converging downwardly, a sleeve to which the lower ends of said additional links are pivoted, said sleeve being slidable upon said rod, a collar spaced below said sleeve and secured to said rod, a coiled compression spring surrounding said rod between said collar and sleeve and exerting an upward stress upon the latter tending to outwardly swing the numerous links from the rod, and means connected with said sleeve for operating an alarm when said sleeve is permitted to slide upwardly by swinging of the links into a cave in the wall of the well.

6. A well cave nder comprising a vertically elongated body, a signal controlling member slidable on said body, an inclined Vil() link pivoted at one end to said member, a second inclined link pivoted at one end to the other end of the first named link, said second link being' pivoted at its other end to said body, spring means tending to move the pivotally Connected ends of said links outwardly to effect sliding of said signaleontrolling member, and an additional and relatively long swingable link extending 10 from the pivotal connected ends of the aforesaid links to a distant point on said body, both ends of said relatively long, link being pivoted and provision being made at one of said ends to permit the necessary sliding movement when all of the links move toward or from the body.

In testimony Wliereotl I have hereunto a'l'lixed my signature.

JAMES J. CABOT.

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